Liquid crystal displays (LCDs) have been mainstream displays. Since the panels of the LCDs are non-self-luminous, lighting devices are required for back-light. In most of the conventional LCDs, light emitting diodes (LEDs) are used to be back-light sources.
According to the position of the LED sources, an LED backlight module can be a side-light type or a direct-light type. Referring to FIG. 1, a diagram showing a structure of a conventional LED backlight module of the side-light type is illustrated. The side-light type LED backlight module 100 mainly comprises a PCB 101, an LED light-source 102 and a light guide plate (LGP) 103. Besides, the backlight module 100 further comprises optical films (not shown) and a plastic frame (not shown).
In this case, the LGP 103 mainly comprises a side light input surface 1031 and a light output surface 1032 opposite thereto. The LED light-source 102 is disposed at one side of the side light input surface 1031. The light emitted by the LED light-source 102 is inputted into the LGP 103 through the side light input surface 1031, and is outputted from the light output surface 1032 by the guiding of the LGP 103.
Referring to FIG. 1 again, there is a specific space between the LED light-source 102 and the LGP 103. When a height h of the light output surface of the LED light-source 102 is less than or equal to a thickness t of the LGP 103, due to an uncontrollable angle of the outputted light of the LED light-source 102, a portion of the outputted light can not be inputted into the LGP 103 and would be leaked from the edges of the LGP 103 (referring to arrows in FIG. 1), resulting a light leakage, thus reducing a luminous efficiency of the LED backlight module.
One solution for the light leakage is that the thickness of the LGP 103 is increased to allow all the outputted light of the LED light-source 102 being inputted into the side light input surface 1031 of the LGP 103. However, this solution does not meet a requirement for lighting and thinning the LCD.
As a result, it is necessary to provide an LED light-source structure and a backlight module to solve the problems existing in the conventional technologies, as described above.